Mafic and ultramafic intrusions observed in the Archean formations of the Sipilou region exhibit occurrences of polymetallic sulphide. Mapping, petrographic and geochemical studies have defined magnetic facies associa...Mafic and ultramafic intrusions observed in the Archean formations of the Sipilou region exhibit occurrences of polymetallic sulphide. Mapping, petrographic and geochemical studies have defined magnetic facies associated with the various geological units. The results of this work reveal that cupronickel sulphides, olivines and pyroxenes as well as spinels are related to ultrabasic formations where strong magnetic facies prevail. Iron sulphides and magnetite are linked to quartzo-feldspathic and jotunite-enderbite formations, which are characterised by moderate magnetic facies. The latter are thought to be derived from anatexite remobilisation within Archean granulites, which have weak magnetic facies.展开更多
This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried o...This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried out on two grids with two magnetometers and an induced polarisation unit composed of a transmitter and a receiver. The magnetic data allowed on one side the mapping of basic, intrusive and volcanic formations, weakly magnetic rocks produced by meta-sediments to be showed, and on the other hand to identify the continuity of the shear corridor observed southward and northward of the prospect. Induced polarisation data revealed the signature of sulphide and disseminated mineralization. The synthesis of the obtained results showed that deep NE-SW, NNE-SSW and N-S oriented fractures promoted the late rise of sulphide fluids. The setting of sulphide and gold mineralization in the southern part of the Boundiali trench is therefore controlled by ductile and brittle shearing.展开更多
This study proposes an alternative approach to the investigation of high flow hydrogeological fractures within the basement in the Dabakala region of north-central Côte d’Ivoire. The used approach consists o...This study proposes an alternative approach to the investigation of high flow hydrogeological fractures within the basement in the Dabakala region of north-central Côte d’Ivoire. The used approach consists of exploring the subsurface by measuring electrical resistivity contrasts along the main shear direction within crystallophyllian rocks. Electrical resistivity profiling and vertical electrical sounding techniques, coupled with boreholes monitoring, have identified fractured aquifers whose best flow rates are around 96 and 116 m<sup>3</sup>/h. These aquifers mostly hosted in granodiorite have an average strength of 10 meters and are located at depth of around 100 meters. They are associated with open fractures created by tangential shear stresses that have affected the Dabakala volcano-sedimentary trench formations. The search for fractured aquifers along the main shear direction offers great perspective for obtaining high flow rates.展开更多
This study enabled us to assess the granite potential on theNonkouagonsite,with a view to meeting the need for supplies of aggregates(essential materials for infrastructure construction).To do this,we began by identif...This study enabled us to assess the granite potential on theNonkouagonsite,with a view to meeting the need for supplies of aggregates(essential materials for infrastructure construction).To do this,we began by identifying the re-sistant zones,comparable to granitic formations,by means of resistivity maps and 2D profiles using the dipole-dipole device.Next,electrical boreholes were drilled with the Schlumberger device in the vicinity of these zones in order to determine the depositional stratigraphy and therefore the rooting depth of the massive rock,which varies between 6 and 30 m.Indeed,the electrical pro-specting made it possible to highlight three lithological groups which are the filling sediments,the volcano-sediments and the basement(granites).The sedimentary formations correspond to the conductive zones,while the base-ment is represented by resistant zones.Finally,to confirm the results of the electrical method,seismic refraction was performed and the interpretation of the seismic section also showed three geological layers.The roof of the granite is observed from a depth of 16 m with a seismic velocity varying from 4.48 km/s to 4.72 km/s.The overlying layers are characterized by seismic velocity which vary from 3.84 km/s to 4.32 km/s for the saprolite and from 3.61 km/s to 3.76 km/s for the alterite.In addition,modelling of the granite areas made it possible to determine the volume of rock and to estimate the exploitable granite reserve at over one million tonnes.展开更多
文摘Mafic and ultramafic intrusions observed in the Archean formations of the Sipilou region exhibit occurrences of polymetallic sulphide. Mapping, petrographic and geochemical studies have defined magnetic facies associated with the various geological units. The results of this work reveal that cupronickel sulphides, olivines and pyroxenes as well as spinels are related to ultrabasic formations where strong magnetic facies prevail. Iron sulphides and magnetite are linked to quartzo-feldspathic and jotunite-enderbite formations, which are characterised by moderate magnetic facies. The latter are thought to be derived from anatexite remobilisation within Archean granulites, which have weak magnetic facies.
文摘This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried out on two grids with two magnetometers and an induced polarisation unit composed of a transmitter and a receiver. The magnetic data allowed on one side the mapping of basic, intrusive and volcanic formations, weakly magnetic rocks produced by meta-sediments to be showed, and on the other hand to identify the continuity of the shear corridor observed southward and northward of the prospect. Induced polarisation data revealed the signature of sulphide and disseminated mineralization. The synthesis of the obtained results showed that deep NE-SW, NNE-SSW and N-S oriented fractures promoted the late rise of sulphide fluids. The setting of sulphide and gold mineralization in the southern part of the Boundiali trench is therefore controlled by ductile and brittle shearing.
文摘This study proposes an alternative approach to the investigation of high flow hydrogeological fractures within the basement in the Dabakala region of north-central Côte d’Ivoire. The used approach consists of exploring the subsurface by measuring electrical resistivity contrasts along the main shear direction within crystallophyllian rocks. Electrical resistivity profiling and vertical electrical sounding techniques, coupled with boreholes monitoring, have identified fractured aquifers whose best flow rates are around 96 and 116 m<sup>3</sup>/h. These aquifers mostly hosted in granodiorite have an average strength of 10 meters and are located at depth of around 100 meters. They are associated with open fractures created by tangential shear stresses that have affected the Dabakala volcano-sedimentary trench formations. The search for fractured aquifers along the main shear direction offers great perspective for obtaining high flow rates.
文摘This study enabled us to assess the granite potential on theNonkouagonsite,with a view to meeting the need for supplies of aggregates(essential materials for infrastructure construction).To do this,we began by identifying the re-sistant zones,comparable to granitic formations,by means of resistivity maps and 2D profiles using the dipole-dipole device.Next,electrical boreholes were drilled with the Schlumberger device in the vicinity of these zones in order to determine the depositional stratigraphy and therefore the rooting depth of the massive rock,which varies between 6 and 30 m.Indeed,the electrical pro-specting made it possible to highlight three lithological groups which are the filling sediments,the volcano-sediments and the basement(granites).The sedimentary formations correspond to the conductive zones,while the base-ment is represented by resistant zones.Finally,to confirm the results of the electrical method,seismic refraction was performed and the interpretation of the seismic section also showed three geological layers.The roof of the granite is observed from a depth of 16 m with a seismic velocity varying from 4.48 km/s to 4.72 km/s.The overlying layers are characterized by seismic velocity which vary from 3.84 km/s to 4.32 km/s for the saprolite and from 3.61 km/s to 3.76 km/s for the alterite.In addition,modelling of the granite areas made it possible to determine the volume of rock and to estimate the exploitable granite reserve at over one million tonnes.
